Hydbomechanical transmission fob



Mud* 12 1940- F. w. coTTERMAN Re. 21,385` "HYDnolEcHANIcAL musn'lssioulion uo'roR vEHIcL'Es original Filed lay 1:5, 1937 2 sheets-Sheet 1INVEN TOR.

Mud* 12. 1.940- F. w. corTERMAN Re. 21,385 HYDRQIBCHNICAL TRANSIISSIONFOR KOTOR VEHICLES y Original Filed lay 13. 1937 2 Sheets-Sheet 2Reissued Mar. l2, 1940 HYDROMECHANICA TRANSMISSION FOI MOTOR VEHICLESFrederick W. Cotter-man. Dayton, Ohio, assigner of one-hal! to Bessie D.Apple, Dayton, Ohio Original No. 2,111,782, dated September 5, 1939,Serial No. 194,637, March 8, 1938, which is a division of Serial No.142,484, May 13, 193'?. Application for reilue October 13. 1939, SerialThis invention is a division of my copending application, Serial No.142,464 (Patent No. 2,134,398) led May 13, 1937, and relates to powertransmission mechanism for connecting a driving 5 and driven member invariable speed ratio, and particularly to that type of transmissionwherein a turbine is combined with toothed gearing to provide a moreextended range. It is particularly adapted to automotive use.

As iswell known inthe art the "Fottinger uid coupling, as applied toautomotive use, comprises a bladed impeller, driven by the engine, and abladed rotor placed adjacent and ln axial alignment with the impeller,the blades being so shaped 15 that the uid circulates in corkscrewfashion between impeller and rotor blades. This device functions merelyas a coupling or clutch, and while slippage between the impeller androtor results in speed reduction, there is not, as is usual M in speedreducing mechanism, any torque multiplication.

As a result of this shortcoming in the fluid coupling, a turbinemechanism has been proposed wherein the blades of the rotor are cut awayfor g5 a part of their length and replaced by blades mounted on aseparate member having means to hold it against rotation. By thisseparate member,- called a stator, the circulation of the iiuid by theimpeller between the rotor blades causes 0 the fluid to react againstthe stator blades whereby the rotor is driven forward at reduced speedand with multiplied torque. 4

A dilculty in the turbine mechanism proposed is that it is required toact both as a clutch and 5 as a torque multiplier and these twofunctions are inconsistent. A

As a clutch for instance, it is required that if the impeller isrotating say 300 R. P. M. and the rotor 3 R. P. M. there will besubstantially zero torque tron, whereas if the mechanism were a perfecttorque multiplier, the torque of the impeller would in this case havebeen multiplied one'hundrediold in the rotor. To obviate this dimcultyin the proposed mechanism, means have-been added to restrain the ow oi'fluid thru the impeller by blocking the space between the impellerblades by valves. These valves are normally closed, but are providedwith centrifugal weights which act at a pre- -determinedjspeed to openthe valves. By this means the impeller does not act as an impeller untila considerable engine speed is reached.

" An inherent diiliculty in the propod mechanisn'i lies in the fact thatthe rotor and stator blades cannot be so designed as to be emcient overa very wide range of speeds, i. e., the eiliciency as a torquemultiplier is at its highest when the speed between the rotor and statoris that for which the blades were designed. The eiliciency, therefore,of the mechanism as a torque multiplier falls of! very rapidly bothabove and below the best speed. It follows that when starting a vehiclefrom a dead stop, particularly on an up grade, the acceleration is notall that could be desired.

As an aid to this condition, the proposed mechanism has added thereto aplanetary gear set comprising, a ring gear, a sun gear and a series ofplanet pinions in mesh with both the ring gear and the sun gear, theplanet pinion carrier being the driven member, the ring gear beingoptionally connectible by manual means either to the housing to hold itagainst rotation for a low geared drive, or to the rotor for higherhydraulic drive, the sun gear being connected to the rotor for the lowgeared drive and to the impeller for the hydraulic drive. 4

Now the difficulty with the proposed arrangement is to manually shiftout of the low geared drive and into the hydraulic drive at the propertime, i. e., at the time the hydraulic unit becomes eilicient enough towarrant discontinuance of the geared drive. There is the furtherdifficulty that the mechanism, functioning as a clutch, never releasescompletely, whereby a manual shift into or out of a toothed connectionbecomes dimcu'lt and necessitates further mechanism to overcome theclutch drag.

It is therefore an object of this Ainvention to provide a combinedhydraulic and geared device of the character described with a. brake forholding the rotorl stationary against the impeller drag, the brake beingoperable on and od thru a mechanical connection between the impellervalves and the brake, whereby, when the valves open to cause theimpeller to become effective to drive the rotor, the brake automaticallyreleases the rotorto be driven, to the end that certain connectionsAwhichare preferably made to the .rotor shaft when it is non-rotativemay be effected by bringing the engine to the idling speed. It isanother object of the invention to provide in a device of thischaracter, a brake of sumcient capacity to hold the rotor non-rotativewhen the engine is revolving at a low speed, and centrifugal weightsoperative at a certain increase in speed of the engine to release thebrake and allow the rotor to be driven.

In` view of the limited speed range withinA which the hydraulic portionof the unit described is emcient, it isa further object of the inventionto` provide a gear box whereby, rather than pull the hydraulic unit downto a ratio at lwhich it multiplies torque at low efficiency, a stepgreater speed reduction between impeller and rotor when it is not vbeingoperated at its maximum capacity, it is a further object of thisinvention to make the step down connection thru the gear box manuallyoperable, whereby, when maximum accelerationjor maximum hill climbingpower is notdesired, the step down connection need not be made.

I n view ofthe fact that vehicle speeds must vary from 5 to 90 M. P. H.,whereas the present internal combustion engines may not be. varied atingFig. 6 is a` fragmentary -section taken at l-O' of 1 showing anotherpart of the mechanism eiiiciently over more than one-fourth this range,it is a further object of this invention to extend the ratio variationthrulthe mechanism by employing gear means and connections therefor,whereby there may be had thru the gearing, an

underdrive, a direct drive and an overdrive ratio,

i the vehicle resistance interposed thereto.

It is a further object of the invention to keep the gear box as compactand inexpensive as possible, and to this end a single gear train,comprising an internal ring gear, a sun gear, and planet pinions, ismade by certain connections to providean overdrive, a direct drive, anunderdrive and a reverse ratio,.the overdrive being controlled bycentrifugal means, and the underdrive and reverse by manual means, whiledirect drive is a normal condition present when neither man-V ual norcentrifugal control is being exercised.

It is a further object to provide, for the manual control, ra, singlepedal of simple construction thru which the gearing maybe operated tounderdrive, reverse, or neutral position, without removing the foot fromthe pedal.

Other' objects and advantages will be more readily seen` as theinvention is described in detail and reference is had to the drawings,wherein;

Fig. 1 is a longitudinal vertical axial section thru the ton mechanism.

Fig. 2 is a fragmentary section taken at 2-2 of Fig. 1 showing part ofthe mechanism'whereby the impeller valves and the rotor brake arecompelled to operate in unison. f

Fig. 3 is a fragmentary section taken at 3-3 of Fig. 1 showing severalof the impeller blades.

4 is a-fragmentary section'taken at 4 4 of Fig. 1 showing thecentrifugal weights for operating the impeller valves and the rotorbrake simultaneously.

Fig. 5 is a fragmentary section taken at l-l of Fig. l showing part ofthe mechanism for opertie rotor brake. I

for loperating the rotor brake;

Fig. 'I is a fragmentary section taken at I--1 of Fig. 1 showing thefront drive shaft clutch Jaws.

Fig. 8 is a transverse section taken at 8--8 of Fig. l showing the frontsun gear clutch jaws.

Fig. 9 is a'transverse section taken at 9--9 ofv 5 Fig. i showing of thelow and reverse operating mechanism.

Fig. 10 is a fragmentary horizontal section taken at III-I0 of' Fig. lshowing the construction of the low and reverse shifting collar.

Fig. 11 is a transverse section taken at lI-II of Fig. 1 thru theplanetary gearing and the clutch jaws of the planet pinion carrier.

Fig. i2 is a transverse section taken at |2-I2 of Fig. 1 showing therear drive shaft clutch jaws and a part of the mechanism for connectingthe gearing to provide an overdrive.

Fig. 13 is a transverse section taken at |3|3 of Fig. 1 thru thecentrifugal mechanism for 1 effecting the overdrive connection. 20

Fig. 14 is a diagrammatic view showing how adjacent faces of clutch jawscarried by the drive shaft and by the sun gear must be beveled to insuresmooth shifting into direct drive.

Fig. 15 is a diagrammatic view showinghow 25 adjacent faces of otherclutch jaws carried by the sun gear and those supported in the housingare beveled to insure smooth shifting intoI low gear and overdrive. l

Fig. 16 is a diagrammatic view showing how 80 adjacent faces of clutchjaws supported in the housing and on the front of the planet pinion.carrier are beveled to insure smooth shifting from direct drive toreverse.

` Fig. 17 is a diagrammatic view showing how 86 adjacent faces of clutchjaws in the tail shaft cylinder and on the outside of the ring gearcarrier are beveled also to insure smooth shifting from direct drive toreverse.

Fig. i8 is a diagrammatic view showing how 40 -adjacent faces of clutchjaws on the front of `planet pinion carrier and in the tail shaftcylinder are beveled to insure smooth shifting from reverse backtodirect drive.

Fig. 19 is a diagrammatic view showing how 45- direct drive to reverse.

Iiig. 21 is a diagrammatic view showing how `liti adjacent fac of clutchjaws on the outsideof the ring gear carrier and on the inside of thetail shaft cylinder are beveled to insure smooth shift-v w ing fromdirect to overdrive.

Fig.22is a diagrammatic viewshowing how adiao0 v cent faces of lclutchjaws canied at the inner pephery vof the rear of the planetpinioncarrier and o n the rear end of the driveshaft are beveled .to smoothshifting from direct to overdrive. Y B5 Fig. 23 is a diagrammatic viewshowing how adjacent faces of clutch jaws in the tail shaft cylinder andonA the front of' the planet pinion carrier are beveled to insure smoothshif from overdrive back to direct drive.

Fig. 24 is auatic view showing how adjacent faces of clutch jaws on therear end of the drive shaft and on the inner periphery of the ring gearcarrierare beveled also to insure smooth shifting from overdrive back todirect. 76

enses is a fragmentary section taken at Fig. l thru the centrifugalmechanism for effecting the overdrive connection. l'ig. 26 ,is afragmentary ysection taken at 26-23 of Fig. 13 thru the centrifugalmechanism for effecting the overdrive connection.

Fig. 27 is a side elevation of the device to a reduced scale showing themanual control.

Where a reference character is med todesignateacertainpartinanyview,itisnotusedto designate a different partin any of the views.

Construction The housing provided to contain the mecha.- nism iscomposed of three sections. The forward section 23 contains thehydraulic unit, therearward section 3Il contains the gear set and thecentrifugal mechanism for connecting the gearing for overdrive, and themiddle section 32 contains the manually operable mechanism for effectingunderdrive. neutral and reverse. Screws 34 secure the front and middlehousing sections together and screws 35 secure the middle and rearsections together.

Within the forward section, the crank shaft 36 of an engine 34- has theimpeller plate 4l se-v cured thereto by the bolts 42 and nuts 44. Theimpeller 46 has blades 46 and is secured to the Vplate 4l by screws 56.

rotor blades 56, in the direction of the arrow 53.

impinges on the stator blades to drive the rotor forward, by forwardbeing meant clockwise when standing at the left of the drawings.

The rotor shaft 68 has rotative bearing at the forward end of thebearing bushing 16 which is press tted in the crank shaft 36, and at therearward end in the bearing bushing 1| which is press fitted in the tailshaft 13. External splines 12, Fig. 6, t between internal splines 'I4 ofthe rotor hub I5 whereby the shaft and rotor always rotate in unison. Acollar 16 is fitted to be slidable axially on the shaft 53. Pins 'l1press ntted in the collarare slidable in holes in the crank shaft 36wherebyvthe collar is compelled to rotate with the crank shaft. Collar'I6 is provided externally. with a coarse pitch thread 1l.

A gear 60 is internally threaded at 32 to fit over the threads 'Il ofthe collar.

Oblong slots 34'inthe gear clear the nuts 44 so that the gear may haveslight rotative movement with respect to the plate 4l. Arcuate openingsI6 thru the gear receive the springs ll and studs ,the shanks of thestuds being rivleied in the plate 46 as at 3|.' The springs 3l alwaysurge the gear Il in the direction of the arrow 33 with respect to theplate 46.

Between the impeller blades 43 are the butterfly valves 62. The valvestems 34 aresquared at I6 where they pass thru the valves, rounded at"and i where theyhave bearing in the impeller, and squared to a smallersize at |32 where they pass thru the centrifugal weights |64. Pinionsegments |66 areintegral with stems `34 and are in constant mesh withthe gear 8l.

A forwardly extending hub Ill having a iiange `m is concenmeauy seemedto the front of the middle housing section 32 by screws ill. The outsideof the rotor hub has rotative bearing in a bushing ||2 press iltted intothe front end of the flanged hub |33. 'l'heA stator body 64 is held by akey ||4 to the stator hub ||6 which is internally formed to receive thecombination roller bearing and roller clutch I8. The flanged hub |63 isexternally formed for the combined clutch and bearing which permits thestator to rotate forwardly but not backwardly.

A thrust bearing |2|l holds the rotor in its forward position. A feltseal washer |22 held by retaining members |24, |26 and |28 keeps thehydraulic duid from leaking out into the housing section 23.

At the rearward end the anged hub lill is internally tapered to receivethe brake cone |36 :vlich is normally held engaged by the spring Awasher |33 held at its periphery between the flanged hub |03 and themiddle housing section 32, receives the reaction of the other end of thespring. The washer |33 also limits -end movement of the rotor shaft 63.

The external splines l2 of the rotor shaft 63 are spaced as for sixsplines but two of the` splines have been cut away (see Fig. 6), and thespace thus made between internal splines 14 of the rotor hub slidablyreceive the keys |34. 'I'he keys |34 are notched at their front end at|36 and the washer |33 is correspondingly notched to t over the keyends. The notched ends of the keys are preferably brazed to the washer|33.

The'cone |36 has internal splines |40 slidably tted to the externalshaft splines 'i2 whereby the cone always rotates with the rotor shaft63. As long therefore as the spring |32 is expanded. the friction of thecone in the tapered end of the hub IUS-keeps the rotor 52 and the shaft58 from rotating. When, however, the cen-- trifugal weights I 04 arecaused by sumcient impeller .speed to y out and open the valves 92. thesegments |36 turn the internally threaded gear Bil, whereupon theexternally threaded collar 16 is moved axially rearward against thewasher which pushes the slidably fitted keys |34 against the cone |30and forces it out of contact with the tapered opening in the hub Theopening of the valves 92 for making the impeller effective as such, musttherefore always occur simultaneous with the freeing of the rotor 52 bythe brake cone |30.

In the forward half of the rear housing section 30 is the planetary geartrain. 'I'he sun gear |42 has a long forwardly extending hub |44 to theinterior of which are press fitted the bearing bushings |46 and |48which are runningiy tted to the rotor shaft 68. Six planet pinions |56are equally spaced about, and in mesh with the. sun gear.

The planet pinion carrier comprises a front section |52 and a rearsection |54 between which the pinions are held. Pianetpinion studs |56are riveted in the rear section and held in the front section by thenuts |58. Bearing bushings |63 are press fitted to the linside of thepinions and runningiy tted over the studs.

The gearing preferably has staggered herringbone teeth so there will beno end thrust under load and therefore, to facilitate assembly,- thering gear vcomprises a front half |62 and a rear half |84, held to thering gear carrier |88 by bolts |88 and nuts |18.

. take the carrier with it and vice versa.

|44 andextends over the ends of the sun gear teeth whereby the washeralways rotates with the sun gear and insures that when vthe sun gearmoves axially on the rotor shaft it must The rear section |54 'of theplanet pinion carrier has press tted therein the bearing bushing |14,which has rotative bearingon the rotor shaft 68.

'I'he ring gear carrier |86 is provided with a press fitted bearingbushing |16 at the forward end and another bushing |18 at its rearwardend, the bushing |18 being runningly fitted over the rear carriersection |84 and the bushing |18 runningly'fitted over the outside of therotor shaft rear clutch member |82.

A split washer |83 is clamped at its periphery between the rear half |84of the ring gear and the ring gear carrier |68. The split washer |83extends into a groove in the re'ar section |84 of the planet pinioncarrier,l its purpose b eing to restrict relative axial movement betweenthe planet pinion carrier and the ring gear carrier.

A ball bearing |84 supported in the rear housing section 38 yprovidesrotative bearing for the tail shaft 13, the bearing being held to theshaft by the screw v|88 acting thru intermediate parts |98, |92, |94 and|98. The forward end of the tail shaft has a ange |88.

'I'he overdrive governor frame 288 has a ange 282 at the rear endconcentricaliy held to the tail shaft flange |98 by the screws 284 (seeFig. 13), and at the forward end the governor frame is bored toslidingly receive the tail shaft jaw clutch ring 288. Ring 288 has aseries of circumferentially spaced ears. 283 movable axially in theslots 288 and held positioned midway of the length of the slots by ap'air of plungers 288 with heads281 backed up by the springs 289. Forconvenience in machining and assembly the rings 2||, 2|3 and 2li areseparate from the governor frame 288 and are held thereto by the screws2|8 (see Fig. 412).

It will be seen that if the jaw clutch ring 288 is moved axially ineither direction it will snap back to the position shown. The governorframe 288 is provided internally with the bearing bushf ing 2|2 which isrunningly tted over the ring gear carrier |88. l i

Rotation of the ring gear carrier in this bushing is had only whileunderdrive is in effect, and never during direct drive, overdrive orreverse. The tail' shaft I3 is held against rearward axial movement bythe bail bearing |84 and against forward axial movement by the washer 2|4 which lrests against a shoulder on the rotor shaft 88.

While neither the tail shaft assembly which includes the-tail shaft 13,governor frame 288 and clutch ring 288, nor the rotor shaft 88 have anyaxial movement in the housing, the entirey gear'assembly including. theplanet pinion carrier andring gear carrier,are slidable axially on therotor shaft, rearwardly to `take `up the space '2|8 and forwardly -totake up the space l 2|8. This axial movement of the gear assembly isutilized to eiect various gear connections necessary to thediferentratios.

Endwise slidable on 'the long sun gear hub An end thrust' oppositelydisposed integral keys 232 extending inwardly into slots which extendvthru the sleeve and the sun gear hub. Because ofthe keys the sun gearhub |44 and the sleeves 228 and 224 must always rotate in unison.

The slots 234 and 236 which extend thru the sleeves 228 and 224 arelonger than the keys 232 so that the keys may be moved axially to someextent in both directions from the position shown in the drawingswithout moving the sleeves directly. When, however, the collar 228 ismoved forwardly or rearwardly, the springs 238 and 249 are energizedandthe sleeves 228 and 224 are urged forwardly or rearwardly by thesprings,

depending on the positionof the collarv 228. A spring ring 229 is placedin a groove in theA sleeve 228.

This ring prevents the anges -222 and 228 from moving farther apart thanshown in the drawings, but does 'not prevent them moving closer togetheragainst the force of the springs 288 and 248. This feature is importantin the functioning of .the mechanism as will hereafter appear. l

The slots 242 thru the sun gear hub |44 are longer than the keys 232only at the rear of the keys. For this reason the collar 228 may moverearwardly without moving the hub |44. The movement howevercompressesvthe spring 248, but if the collar is moved forwardly, it mustdrag the entire gear assembly forwardly with it. To facilitate assembly,the collar 228 is made in halves'. held together by the screws 244 (seeFig.

. 9), extending thru ears 248.

A shifting fork 248 is swingable by the splined shaft 248 which hasrotative bearing in the hubs 288 and 282 of the middle housing section32. Rollers 284 (see Fig. 9) are rotatable on studs 258 secured in thefree ends of the fork. The rollers 284 nt the groove 238 closely butrunningly. The forward side of the shifting fork 248 is flattened at 288 and a hollow plunger288 is` pressed against the attened surface bythe heavy spring 282. 1

The fork hub is further cut away at 284 so that the springs 282 need notbe compressed as much when the collar Y228 is moved forwardly as when itis moved rearwardly. The reason for 'desiring this difference inpressure will later appear.

The overdrive governor'frame 288 has two ribs 288, each thick enough tocontain a plunger 288 backed up by a heavy spring 288 and a plunger 218backed up by a lighter spring 212.v The frame also carries ribs 214,(see Fig. 12) which termi` nates' at their rear edges in hinge-ears .216.(see Figs. 13iand 26) The governor weights 2184 each have a pair of'hinge ears 288 and 282 (see F1g. 25), extending forwardly between theframe ears 218. Hinge pins 284 extend thru both the frame'ears andtheweight ears-to-hingedly support. the weights on.

circular groove 266 in the rearend of the ring gear carrier |66 wherebyinward or outward movement of the weights 216 rocks the arm forward orrearward and thereby moves the gear assembly forward or rearward formaking different connections for different ratios.

At the extreme free end of each arm 266 is the segment 296 so shapedthat the detent plunger 300 backed u'p by the spring 302 resistsswinging of the arm about the hinge pin in the direction caused byoutward movement of the weight, but does not resist swinging of the armabout the hinge pin in the direction caused by inward movement of theweight.

A notch 304 in the edge of th segment tends to keep the arm located inits rearward position when the plunger 300 is pressed into the notch bythe spring 302.

Outward movement of the weights 216 is resisted by the heavy springs 266acting thru plungers 266 and by the springs 302 acting thru detentplungers 300, while inward movement of the weights is resisted only bythe light springs 212 acting thru plungers 210. Outward movement of theweights 218 is caused only by centrifugal force, while inward movementoccurs only when `the gear assembly is drawn forward by forward movementof the collar 226 acting thru the keys 232 against the front end of theslots 242 of the sun gear hub |44. The flanges ISB and 202 are notchedat 303 to clear the weights 216.

On the forward end of the long sun gear hub |44 are formed the clutchjaws 304. On the forward end of the sleeve 220 are formed the clutchjaws 306. The faces of the jaws 304 are beveled at 303, Fig. 20, whilethe faces of the jaws 306 are beveled just oppositely as at 3|0, Fig.14.

Integral with the rotor shaft 66 are three segmental lugs (see Fig. 7),the inner halves 3|2 of which are thicker (see Fig. 1), than the otherhalves 3|4, the inner halves having their faces beveled as at 3I6, Fig.20, and the outer halves having their faces beveled just oppositely, asat 3|6. Fig. 14.

The sun gear jaws 304 are adapted to. be received in the spaces betweenthe rotor shaft jaws 3|2 when the gear assembly is drawn forward bymeans of the collar 220, while the sleeve jaws 306 are adapted to bereceived in the spaces between the rotor shaft jaws 3 I4 whenever thespring 236 is energized to a greater extent than the spring 240 which isthe condition present when the mechanism is as shown in Fig. l of thedrawings, i. e., with the jaws 306 and 3I4 meshed.

As above described there are two sets of clutch jaws, both forconnecting the sun gear to the rotor shaft, one set having the jaw facesbeveledin one direction and the other set having the jaw faces beveledopposite to the first set, the reason being that, under one drivingcondition, the sun gear must connect to the rotor shaft when the rotorshaft is just passing the sun gear in speed, while under another drivingcondition the sun gear must connect tc. the rotor shaft when the sungear is just passing the rotor shaft in speed. l

Around the periphery of the flange 226 are the external clutch jaws 320.The rear faces of these jaws are beveled as at 322, Fig; 15. Clampedbetween the middle and rear housing sections 32 and 30 by the screws 35is a clutch ring 324 having internal jaws 326 beveled on their front andrear races as at 326 and 330, Figs. 15 and 16.

Within the tail shaft clutch ring 236 are three axially spaced sets ofjaws, the forwardset 332,

the middle set 334 and the rear set 336. The forward set 332 has itsfront and rear faces beveled as at 333 and 340, Figs. 18 and 23. Themiddle set 334 has its front and rear faces beveled as at 342 and 344,Fig. 17. 'Ihe rear set 336 has its front and rear faces left straight asat 346, Fig. 21.

At the periphery of the front section |52 of the lplanet pinion carrierare .the jaws 346 (see Fig. 11), beveled on their front and rear facesas at 366 and 352, see Figs. 16, 18 and 23.

At the periphery of the ring gear carrier |66 are the jaws 354, beveledon their front faces as at 366, but plain on the rear faces as at 358,Figs. 17 and 21.

On the outside of the rear section |54 of the u planet pinion carrierare the jaws 360, beveled on their rear faces only as at 362, Fig. 22.

On the inside of the ring gear carrier |66 are the jaws 264 (see Fig.12) beveled on the front and rear faces as at 366 and 366, Figs. 19 and24.

.On the outside of the rotor shaft rear clutch member |62 are the jaws310, straight on their front faces as at 312 and beveled on their rearfaces as at 314, Figs. 19, 2 2 and 24.

The rotor shaft 66 has splines 316 on the rear end (see Fig. 13), andthe clutch member |62 hasinternal splines 311 axially slidable over theshaft splines. A hole 316 is drilled in the rear end of the shaft 66 anda slot 360 extends crosswise thru the shaft and hole. A rectangular bar362 is freely fitted to the slot and is held to the rear of the slot bythe spring 364 which is within the hole 316. The bar 362 has only abouthalf the axial dimension of the slot, whereby the bar may move axiallyforward againstv the stress of the spring. The bar 362 not only restsagainst the rear edge of the slot 360, but its outer ends rest againstthe ends of two of the internal splines 311 of the clutch member |62.

' Surrounding the-end of the shaft 66 Where there are no splines is thespring 366, one end f which rests against the washer 2|4 and the otheragainst the ends of the shaft splines 316 as well as the ends of theinternal splines 311.

The structure provides means whereby the vclutch member |62 isresiliently held in the axial location shown. If it is moved axiallyforward, the spring 364 will be compressed, but the spring 366 will notfurther expand, and if it is moved axially rearward, the spring 366 willbe compressed but the spring 364 will not further expand. 'I'he clutchmember |62 will therefore snap back to the exact position shown nomatter in which axial direction it has been moved.

Rigidly secured to the outer end of the splined shaft 246 is the pedal366 (see Fig. 27). shaft 246 and the hub 252 (see Fig. 9) are prolongedsufllciently to locate the pedal in the position occupied inconventional practice, by the clutch pedal, i. e., fn the positionsuitable for operation with the drivers left foot. Downward pressure onthe pedal by the toe will move the collar 226 rearward to effect theunderdrive connection, while downward pressure on the pedal by the heelwill move the collar forward for reverse connection. 'I'he floorboardline is at 330 and the toeboard at 392. A pocket 394 is depressed in theoorboard, somewhat wider than the pedal, at the heel end thereof. Aneutral' position'involving complete disconnection of the rotor shaftfrom the tail shaft is had when the heel end of the rotate it fasterthan the speed at which theimpeller valves open and movement of thevehicle begins.

Proportion While the mechanism shown may be proportioned for use withany horsepower and vehicle weight within reason, some suggestion as tothe proportion for a given vehicle may preferably be given.

If the largest dimension of the housing 28 is taken as 151/2" and otherparts made to the same scale, the mechanism will be suitable for anengine of around 100 PL' P. in a vehicle of approximately 3500 poundweight.

The planetary gearing are 16 pitch 20 degree pressure angle, 14 degrees55 minutes helix angle. The ring gear has 60 teeth on a pitch diameterof 3.8808"; the sun gear 30 teeth on the pitch diameter of 1.9404"; andthe 'planet pinions 15 teeth on a pitch diameter of .9702".

The underdrive ratio, provided by making the' ring gear the driver, theplanet pinion carrier the driven, and the sun gear the stationarymember, will then be %=63g=2 rotor shaft revolutions to 'produce 1 -tailshaft revolution.

With a '4 to 1 rear axle and the hydraulic unit loaded so as to pull itdown to a ratio of 2 impeller revolutions to one rotor revolution, whichis within the eflicient range as a torque converter, the totalengine-to-wheel ratio thruunderdrive would be 2 4=12; thruv direct 5%.But in either of these gear connections, the .torqueconverter wouldgradually, as the engine' was able to increase its speed under the load,change from 2 to l, to 1 to 1. whereupon the engine-to-wheel ratio wouldbe,for underdrive 6 to 1; for direct 4 to i, and for overdrive 2% to 1.

The range of engine-to-wheel ratio change is therefore usually somewherebetween 12 to l and 2% to 1, depending on to what extent the ratio ofthe hydraulic lmit is pulled down, or allowed to so Aup by variationbetween the power being planet pinion carrier the stationary member willgenerated and the vehicle resistance being encountered. Similarly thereverse ratio mayvary from 16 to l, to8 to 1, depending on the resistfance encountered.

Inthe hydraulic unit,-the centrifugal weights |08, and the springs 88and |32 are so proportioned that the weights fly out and open theimpeller valves and release the rotor brake at about 600 engine 1R. P.M. This may of course be varied `to suit individual engines.

In the gear box, the centrifugal weights 218 and their restrainingsprings 268 and 302 are preferably so proportioned that the weights willmove to connect for overdrive ratio at around 50 M. P. H., however,sincethe rear axle ratio must be varied somewhat from the 4 to 1 valuegiven, becoming greater as the vehicle weight is greater and the enginepower less, so the overdrive ratio may profitably be varied, i. e., tocome in at a lower speed if the proportion of engine power to vehicleweight justifies with the axle ratio selected.

Operation The normal condition of the mechanism, i. e., the conditionwhich exists when the engine is at rest or operating below 600 R.. P.M., is that shown in the drawings, where vthe centrifugal weights |04 ofthe hydraulic unit are in their in" position and the rotor brake |30 isapplied, and where the gear mechanism is coupled for direct drive, i.e., for connection between the rotor shaft and tail shaft which compelsthem to revolve at the same speed. 'I'his coupling exists by virtue ofthe fact that the sun gear and the ring gear are both connected torevolve with the rotor shaft, and the planet pinion carrier is connectedto revolve with the, tail shaft, no member being held stationary.

The greater percentage of all forward driving will vbe done with thegear mechanism'in direct drive as shown. If, for instance, a driver isstarting the vehicle on a substantially level road and is contentwithgood, but not maximum acceleration, he need only depress the engineaccelerator whereupon the engine 'will first increase to 600 R. P. M.,open the impeller valves and release the rotor brake, thereby drivingtherotor at a less speed and greater torque than the engine.

A hydraulic torque converter similar to that `herein shown has alreadybeen developed by others to a degree which provides torquemultiplication somewhat better than is had with the second gear of aconventional gear box. Inasmuoh as many drivers of conventional vehiclesstart -irom a dead stop in second gear, such drivers at least would besatised with the acceleration ob- Itainable thru the hydraulic unitAherein `shown without further torque multiplication thru the gearmechanism. f

Other driving conditions, however, require the use ofthe gearing, as forinstance, where the driver has started the engine in the usual mannerand it is cold, and he desires to speed up the en gine beyond 600 R.. P.M. to warm it without driving the vehicle. In this case he allows hisfoot to slide heelward on the pedal until the back of his heel touchesthe wall 388. (see Fig. 27). He then presses the heel end of the pedal388 down until the bottom of his heel strikes the projection 886. Indoing this he has drawn the gear assembly forward with the collar 228until the jaws 840 of the carrier section |02 are out of engagement withthe tail shaft jaws 832 but not far enough to have engaged thestationaryjaws 820. Similarly the jaws 30| of the ring gear carrier havemoved out of engagement with the jawsl'll, of theclutch aus member |82.The sun gear jaws 304 have moved forward but not enough to engage thejaws 3|! of the drive shaft. In this condition there is no drivingconnection between the rotor shaft and tail shaft. In this neutralposition the engine may be speeded up and warmed.

Assuming that the driver next desires to back the vehicle. To do this heflrst lowers the engine R. P. M. to the idling speed by releasing theaccelerator pedal, then places his foot on the pedal 333 as shown inFig. 27 and presses the heel downward. To make the reverse connectionthe jaws 304 of the sun gear must mesh with the jaws 3|! of the rotorshaft, the jaws 348 of the planet pinion carrier must mesh with the jaws326 of lthe stationary ring, and the `jaws 354 of the ring gear carriermust mesh with the jaws 334 of the tail shaft ring. The connectionsshown in the drawings between the lplanet pinion carrier and the tailshaft and between the ring gear carrier and the rotor shaft will, ofcourse, be rst 'unmade.

Since it is highly improbable that all these sets of jaws to be meshedwill be in meshing alignment when the heel is pressed downward, itfollows that the faces of at least some of the jaws will come together,but power is now applied to` turn the rotor shaft, whereupon the firstset to be meshed will have relative movement as indicated by the arrowsin Fig. 20, the second set will have relative movement as indicated bythe arrows in Fig. 16, and the third set have relative movement asindicated by the arrows in Fig. 17.

The space '2 I3 (see Fig. 1), thru which the jaws 304 must move to reachthe jaws 3|! is slightly less than the spaces thru which the other jawsto be meshed must move. so that the rotor shaft motion will always startthe sun gear rotating 'rst.

Rotation, of the remaining jaws to be meshed will naturally follow, and,the faces being beveled as shown, the jaws will move, each down thebeveled faces of the other into mesh, if a slight foot pressure ismaintained after the accelerator is depressed. Should the jaws 348become aligned with the jaws 326 before the jaws 354 become aligned withthe jaws 334, the jaws 348 may at once enter because of the yieldablemanner in which the jaws 334 are held positioned by the springs 209 andplunger heads 201.

When the gear assembly is drawn forward as above explained to make thereverse connection, the ring gear carrier groove 236 (see Fig. l) is,4of course drawn forward with it. The roller 292,

the direction of the arrow 402, Fig. 26, and causes the weight 218 toswing inwardly against theplunger 210 and spring 212, Fig. 1. The lowspeed at which a vehicle is driven backward produces a very slightcentrifugal force in the weights 213 which must be overcome by the pedalalong with the force of the spring 212.

In order to lessen the force necessary to press down the pedal forreverse connection, the shifting fork 246 is cut away as at 264, so thatthe spring 232 is compressed less in pressing the pedal 383 with theheel than when pressing it with the toe. The springs 238, 262 and 212,each provide part of the resistance offered to the pedal in making thereverse connection. v

Assume that the vehicle has been moved backwaidly as desired and thepressure is removed from the pedal to allow it to return to the normalposition shown in Fig. 2'1. This should remake i the direct driveconnection. The expansion of 73 the springs 238 and 232 immediatelyreturn the pedal and the collar 223, but unless both sets of jaws whichhave to be reengaged are in meshing alignment, which is unlikely, thespring 21! may not instantly expand, but will hold the faces of the jawstogether resiliently until they may mesh. The jaws which must beremeshed when shifting out of reverse back to'direct are, the carrierjaws 348 with the tail shaft jaws 332, and the ring gear jaws 364 withthe rotor shaft jaws 310.

When release of the heel pressure from the pedal has allowed the facesof these two sets of jaws to be resiliently pressed together, the powermay be applied to turn the rotor shaft. whereupon relative motion of thejaws 343 with 332 and of the jaws 364 with 310 will be according to thearrows in Figs. l8 and 19 respectively. By reference to,Figs. 18 and 19,it will be seen that the faces of the jaws seeking engagement are sobeveled that when they are held together resiliently and rotationstarted, the jaws will slide down the inclined faces into mesh.

If, during the above reentry, the jaws 348 and 332 are aligned forreentry with each other before the jaws 364 and 310, or vice versa, thefact that the jaws 332 and the jaws 310 are yieldably held to thepositions shown by springs 209 'and 336 respectively, will permit eitherto mesh ahead of the other.

It willbe apparent that it will not be best to have two sets of jawswhich must be meshed at j the same time unless each set wasindependently sprung, inasmuch as a rotating`condition might be hadwhere, when either set of jaws were aligned to enter, they would be heldapart because of the fact that the other set was at that timemisaligned. It is at least apparent that entry of two sets may be morereadily made-if eachis individually sprung.

Assume the driver now wishes to use underdrive to move the vehicleforward with maximum acceleration. For making this connection he pressesthe pedal 333 all the way down with the toe end of his foot. The firstresult had is, that the collar 223 moves rearward and its keys 232 mnvein spaces 234, 236 and 242. The gear assembly does not move because ofthe springs 233 and 212 acting on the plungers 266 and 210 hold the arn.233 and roller 28! rigid. The slots 242 in the sun gear hub are of suchlength that, at maximum pedal depression, the keys 232 just touch therear ends of the slots, but the slot 234 'is so much shorter than theslot 242 that the maximum pedal depression causes the keys 232 to pullthe jaws 306 half out of mesh with the jaws 3|4. Now by consideringFigs. 14 to 24, it

will be seen that the amount of bevel on the sides of the beveled jawsis one-fourth'the whole jaw thickness. It follows that when a4 pair ofsuch jaws are meshed half way-or less they drive in one direction butwill overrun in the other. They will drive in one direction but ratchetover in the other direction up'to half way mesh, but either one willdrive both directions after it is4 more than half way meshed.

Besides having pulled the jaws 303 half out of mesh with the jaws 3|4and made a one way drive of them, the pedal depression also greatlyincreased the stored energy in the spring 240 and jaws 310 and ring gearjaws 334 are fully meshed.

The vehicle resistance now tries to hold the tail shaft, andconsequently the planet pinion carrier. from rotating, whichresults inthe sun gear starting to rotate backwardly, which it may do because theVjaws 366 mayfratchet backwardly over the jaws 3I6 (see Fig. 14), theirrelative Now the snap ring 229 is so placed that when the jaws 366 arepulled half way out of mesh the jaws 326 may go half way .into mesh butnot farther, and when the jaws 326 move more than half in, the jaws 366are drawn more than half out, so that by the time the jaws 326 are fullymeshed, the jaws 366 are fully unmeshed.

The foregoing described a shift' from direct to g underdrive when thevehicle was at rest, but it is also desirable that a shift from directto underdrive may easily be made `at high vehicle speed, as forinstance, when a steep grade is encountered.

'In such a case the operator preferably rst releases the acceleratorpedal momentarily, then depresses the toe end of the control pedal,thereby pulling the jaws 366 half out of mesh as well as pressing thefaces of the jaws 326 resiliently against the faces of the jaws 326.`

The accelerator being released, the vehicle movement tries to rotate thesun gear forwardly but the half meshed jaws 366 prevent the sun gearrotating forwardly faster than the engine, that is, they drive theengine by vehicle momentum. Thel jaws 326-,.moving forwardly will ofcourse ratchet over the jaws 326 (see Fig. 15), until power is appliedto the engine, whereupon the sun gear tries to rotate backwardly, andwhen it does, the full meshing of the jaws 326 and 326 takes place forunderdrlve as before explained. It will be seen that in the transitionperiod there was no free wheeling, that is, the vehicle still drove theengine after the pedal was operated and the engine drove the vehicle assoon ,as power was applied. 'There is no point at which the engine andvehicle are completely separated as they are in the shift of commonpractice.

Now if, while'operating in underdrive at high speed, it becomesdesirable to return to direct drive, the control vpedal is merelyreleased and the collar 226 will return to the normal position shownAltho the springs 236 are'now placed in much. greater stress than thesprings 266, the jaws 326 may not move out of mesh with the 'jaws 326until the accelerator'is sumciently released to relieve the frictionbetween the driving surfaces of the jaws.' j

When, however, the tension between these driving faces isrelieved, thejaws 326 will be drawn half wayout of mesh, by engagement of the forwardend of key 4232 withthe forward end of the slot 236, and the faces ofthe jaws 366 pressed resiliently into contact with the faces of thefjaws3M. .Inasmuch as the sun gear was non-rotative when theaccelerator wasreleased,

` the jaws 3I6 may ratchet over the non-rotating jaws 366 (see'Fig. 14),even tho they are half meshed, until the engine speed reduces to a pointwhere the vehicle tries -to drive the engine, whereupon the sun gearwill try to rotate forwardly and the. jaws 366 will .slide down theinclined faces of vthe jaws 3i6 and into mesh.

When they are halfway mashed, the springring 229 .encounters theshoulder inthe sleeve 236 and the jaws 326 are pulledv clear out of meshas the jaws 366` go clear into mesh.

The overdrive gear connection will be made nasse automatically wheneverthe accelerator is released, so as to move the friction from the jawswhich are carrying the load, the weights will move out and, thru thearms 266 and rollers 292, draw the entire gearlassembly rearward. Thestraight faces 366 of the ring gear jaws 366 are pressed against theystraight faces 366 of the rear Vtail shaft jaws 336 (see Fig. 21).

Similarly, the straight faces 362 of the planet pinion carrierjaws 366are pressed into contact with the straight faces 312 of the rear driveshaft jaws 3,16 (see Fig. 22). Since all of these jaws are revolving atthe same speed when pressed together there is no necessity of having thefaces of these jaws beveled to permit overrunning, but unless these twosets of jaws are aligned for entry, the jaws 336 and 316 will.

be displaced rearwardly, against the resistance of springs 269 and 366respectively, a distance equal to their thickness, in order that theweights 216 may move all the way out at once.

'Ihe weights ln thus moving out and moving the gear assembly rearward,also draw the collar 226 rearward and the toe `end of the control pedal366 down exactly as they are operated man` ually when shifting fromdirect to overdrive, the jaws 3I6 being pulled half out of mesh toratcheting position and the jaws 326 being resiliently held against thejaws-326.

j Dropping of the engine speed now produces re1- ative movement of thejaws-3H and 366 as in Fig. 14, and relative movement of the jaws 326 and326 as in Fig; 15. 'Ihe remaining jaws 366 with 336, and 366 with 316which are pressed tol'gether resiliently may drive by frictionsumciently to turn the jaws 326 to meshing position (see Fig.k l5), or,if they slip ever so slightly, they drawing-s. Three sets of jaws areagain pressed together resiliently, sus against au (see Fig. 14), 366against 332 (see Fig. 23), and 366 against 316 l(see Fig. 24).Ratcheting between the several jaws of each pair will occur, therelative lmovement being as indicated by the arrows in Figs. 14, 23 and24,` until the rotor shaft speed again is brought up tothe tail shaftspeed which maybe done by a touch of the accelerator pedal.

While the mechanism herein shown and 1described includes ahydraulictorque converter with a mechanical gear-set in series and is thus shownin order to disclose a complete operative structure, the followingclaims are drawn to the novel features of the4 hydraulic unit only,claims to the gear-set being contained in the .parent applicationhereinbefore referred to.

enses power transmitting devi, oi' an impeller, a

I claiml. In a iiuid coupling of the Fttinger type comprising, animpeller and a rotor, the combination with vmeans loperative tosubstantially block circulation of the iluid,l braking means to hold therotor non-rotative while said blocking means is operative, and meansresponsive to impeller speed tosimultaneously' operate the blockingmeans to inoperative position and the braking means to releasedposition.

2. In power transmission mechanism, an impeller, a rotor adapted to bedriven by said impeller, valve means for closing the spaces between theimpeller blades, a brake for holding the rotor against rotation, speedresponsive means for opening said valve means at a predeterminedimpeller speed, and means connecting said valve means and said brakewhereby opening said valve means releases said brake.

3. A uid coupling of the Fottinger type comprising an impeller and arotor in combination with means applicable to substantially blockcirculation of the fluid,'braking means applicable to hold the rotornon-rotative while said blocking means is applied,and a'centrifugaldevice rotated by the impeller and operative at a predetermined speed tosimultaneously release said blocking and said braking means.

4. Hydromechanicai power transmission mechanism comprising, incombination, an impeller, a

rotor, valve means normally closed to prevent circulation of iiuidbetween the impeller and rotor, a brake holding the rotor non-rotative,and a centrifugal device operative at a predetermined speed tosimultaneously lopen the valve means and release the brake.

5. Fluid transmission mechanism of the character described having animpeller and a rotor in combination with means normally retardingcirculation of duid therebetween, means normally restraining rotation ofthe rotor, a normally unoperated speed responsive device, and meansconnecting the said retarding and restraining means to the speedresponsive device, whereby said stems outside the other said shroud, a

operation of the speed responsive device releases said retarding andsaid restraining means.

6. A uid power transmission device comprising in combination, a bladedimpeller, a rotor, valve means adapted to close the space between theimpeller blades to keep it inactive, a brake holding the rotornon-rotative, centrifugal weights on the impeller operable outwardly toopen said valve means, and means connecting said valve means and brakevwhereby operation oi' s aid weights opens the valves and releases thebrake.

7. A iiuid power' transmitting device comprising, in combination, abladed impeller, a' rotor,

valves between the impeller blades closed to keep' the impellerinactive, a brake holding the rotor non-rotative, centrifugal weights onthe valves operable at a predetermined speed to open the stems oi' thebutteriiy valves swingable outwardly at a predetermined vspeed to opensaid valves, and means connecting the valves and said brake wherebyopening said valves releases said brake. 9. 'nie combination. in ahydromechanical rotor, butterily valves closing the spaces between l0.In combination, an impeller, a rotor, butterfiy valves closing thespaces between the impeller blades, centrifugal weights on the stems ofsaid valves for rotating said valves to open position 'at apredetermined impeller speed, pin'- ions on said stems, a gear in meshwith said pinions, a brake holding said rotor non-rotative but operableaxially to release said motor, and means operative by rotation oi' saidgear to create an axial pressure against said brake to release saidbrake.'

11. In combination, an impeller, a coaxial rotor, axiallyparallel stemsbetween the rotor blades, butterfly valves on said stems, centriIu-f galweights on said stems swingable outwardly to rotate said stems and opensaid valves, pinion segmentssonysaid stems, a coaxial gear` in mesh withsaid pinion segments, screw and nut means operable axiallyv by rotationof said gear, an axially applied brake holding said rotor non-rotative,and means connecting said screw and nut means to said brake wherebyoperation of said weights opens said valves and releases said braise.

12. Fluid power transmission mechanism comprising, in combination. abladedA rotor, a coaxial bladed impeller having shrouds on each side ofthe blades, axially parallel stems between the impeller blades havingrotative bearing in ing the spaces between the impeller blades,centrii'ugal weights on said stems outside one of the shroudsl andswingable outwardly to rotate said stems and open said valves, pinionsegments on coaxial gear in mesh with said pinion segments and rotatablethereby, screw and nut means as.

sociated with said gear operable axially by rota- -tion oi' said gear, abrake element carried by said rotor urged axially into engagement withva nonrotatable element to hold said rotor nonrotative, resilient meansurging said brake element axially into engagement, and'means extendingfrom said. 4screw and nut means to said brake element operable, by axialmovement oi' said vscrew and nut means, to move said brake elementagainst said resilient means to release said brake.

13. In a power transmission, an impeller. centrifugal weights carried bysaid impeller, a rotor, a rotatable brake part carried by said rotor anddriven at rotor speed, a non-rotative brake part,

means for engaging said rotatable brake part with the non-rotative brakepart, and connecting means between said 'centrifugal weights and saidrotatable brake part whereby rotation o! said impeller aboveapredetermined speed operates said weights to overcome said `brake engaging means and move said rotatable brake partout of engagement withsaid non-rotative brake part thru said connecting means.

14. IHydraulic power on m non-rotative brake member, means for engagingthe two said brake members. and means connecting said speed responsivemeans and said rotatable brake member whereby operation of said impellerabove a predetermined speed withdraws said rotatable brake member fromsaid `non-rotative brake member to allow said rotor to rotate. v

15. 'Power transmission mechanism of the character described,comprisingr an engine,an impeller driven at engine speed, a speedresponsive device driven at engine speed, a rotor. a brake having onemember carried by said rotor and the other non-rotative, adaptedwhenapplied to hold said rotor against rotation, and means con-l nectingsaid sp'eed responsive device and said brake whereby a predeterminedrise in engine speed releases said brake. p

16. Hydraulic transmission mechanism comprising, an impeller. a rotor, aspeed responsive device sensitive to change in Iimpeller speed, a

a1,ses

rotor brake -comprising two parts adapted to be engaged to hold saidrotor non-rotative, and a means connecting said speed responsive deviceto one of said brake parts whereby operation o! said impeller above aselected speed Vwithdraws one of said brake parts from the other to freesaid rotor for rotation.

17. In a power transmitting device o! the charlacter described',- animpeller, a rotor. brake ior holding the rotor against rotation,mechanical `linkage for releasing said brake, and a device operated bythe impeller and operative upon a predetermined rise in impeller speedto move said linkage to 4disengage said brake.

18. Power transmitting mechanism comprising, an impeller, a rotor, arotor brake, and mechanism responsive to variations in impeller speedoperative upon a selected rise in impeller speed to release said brake.

COTTERMAN.

